From owner-freebsd-arch Sat Oct 12 12:27:36 2002 Delivered-To: freebsd-arch@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 5EF1437B404; Sat, 12 Oct 2002 12:27:35 -0700 (PDT) Received: from mail.chesapeake.net (chesapeake.net [205.130.220.14]) by mx1.FreeBSD.org (Postfix) with ESMTP id 7EA4D43ED1; Sat, 12 Oct 2002 12:27:33 -0700 (PDT) (envelope-from jroberson@chesapeake.net) Received: from localhost (jroberson@localhost) by mail.chesapeake.net (8.11.6/8.11.6) with ESMTP id g9CJRK196235; Sat, 12 Oct 2002 15:27:20 -0400 (EDT) (envelope-from jroberson@chesapeake.net) Date: Sat, 12 Oct 2002 15:27:19 -0400 (EDT) From: Jeff Roberson To: Julian Elischer Cc: Hiten Pandya , Terry Lambert , Jeff Roberson , Subject: Re: Scheduler patch, ready for commit. In-Reply-To: Message-ID: <20021012152434.U30714-100000@mail.chesapeake.net> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-arch@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG On Sat, 12 Oct 2002, Julian Elischer wrote: > On Sat, 12 Oct 2002, Hiten Pandya wrote: > > > On Thu, Oct 10, 2002 at 01:18:44AM -0700, Terry Lambert wrote the words in effect of: > > > > Yes, I agree, this is an important next step. I'm thinking that the > > > > scheduler should indicate how much space is needed to the proc allocation > > > > code. This much extra space could be allocated, and a pointer to > > > > scheduler specific data could really be a pointer within that allocated > > > > structure. This way it might be near enough for processor caches to be > > > > effective. Clearly this needs more work. That is outside of the scope of > > > > the current patch though. > > If done on the fly, this would require freeing all the allocated procs > in the uma cache and changing the size of the zone, and re-filling it, > and replacing all the existing procs with the new larger ones.. hardly a > likely scenario. > Pretty obviously the additional storage is in the form of an extra blobb > hanging off the proc/kse/ksegrp/thread structures as needed. (Unless the > scheduler can make use of a couple of void * 'p_sched_private' type > fields we can preallocate. > Is there really demand for on the fly scheduler changes? I guess I always thought of it as a neat trick and not something useful. It doesnt seem like it's worth the overhead for the extremely small number of scenarios where it's needed. Cheers, Jeff To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-arch" in the body of the message